This invention relates generally to caster wheel assemblies, and more particularly to an improved caster swivel assembly for rotationally mounting a support wheel to a frame of baby furniture such as a stroller and the like.
Baby furniture, particularly infant strollers, use caster wheel assemblies to provide directional maneuverability. A caster swivel connection for the wheels at the front of the stroller provides improved maneuverability and directional control for the users. In some cases, casters are used at each leg of the stroller. Due to the relatively light loads imparted on infant strollers, it is common to employ caster assemblies which use rotational bushings rather than bearing assemblies to reduce cost and weight while still providing smooth rotational movement. Conventionally, a single wheel or tandem wheel assembly is supported by an axle and retained by a swivel housing. A leg of the stroller frame is connected to a bushing which is rotationally disposed in the swivel housing. Various constructions are used to retain the bushing in the housing. U.S. Pat. No. 4,897,895, for example, discloses the use of a detent on a bushing to retain the bushing in the caster housing while allowing rotational movement. U.S. Pat. No. 5,237,721, the disclosure of which is hereby incorporated by reference, discloses a swivel caster assembly having a load bearing bushing rotationally disposed in the caster body having a wheel axle supporting aperture. Other constructions are known.
Known swivel caster assemblies of the type typically found in infant strollers afford excellent maneuverability on smooth support surfaces, such as ordinary sidewalks, driveways and the like. However, the normal free swiveling action of such caster assemblies is a disadvantage when the stroller encounters rough terrain, such as an earthen path with ruts, rocks or other obstructions. More particularly, because of the relative ease with which the support wheels can be swiveled in the caster assembly, the wheels tend to readily follow the irregular contours encountered which results, at best, in a rough and bumpy ride experienced by the infant in the stroller and, at worst, tipping or upsetting of the stroller itself. While the former reaction is merely discomforting to the infant, the latter can be dangerous. Attempts to minimize or eliminate the problem of erratic swiveling in rough terrain have included providing disengageable locking mechanisms which prevent rotation of the caster assembly. However, known solutions suffer from the disadvantages of relatively complicated structure, relatively high incremental cost and relative difficulty in use.